Bowling ball lift control mechanism



March 1, 1966 H. c. CONGELLI 3,237,943

BOWLING BALL LIFT CONTROL MECHANISM Filed May 18, 1962 4 Sheets-Sheet 1 FIG.I

I HEN RY C. CONGELLI ATTQRNEY March L flfi H. c. CONGELLI 3,237,943

BOWLING BALL LIFT CONTROL MECHANISM Filed May 18. 1962 4 Sheets-Sheet 2 26 i Q I I i 5 45' E 72 INVENTOR. /7 27 HENRY C.CONGELL1 ATTORNEY March 1, 1966 H. c. CONGELLI 3,237,943

BOWLING BALL LIFT CONTROL MECHANISM Filed May 18. 1962 4 Sheets-Sheet 4 'IIIIIIIIII INVENTOR. HENRY C.CONGELL| ATTORNEY United States Patent l 3,237,943 BQWUNG BALL LIFT CGNTRGL MECHANISM Henry C. Congelli, Stamford, Conn, assignor to American Machine dz Foundry Company, a corporation of New .lersey Filed May 18, 1962, Ser. No. 195,920 12 Claims. (Cl. 273-49) This invention relates to bowling ball lifting mechanisms and, more particularly, to such mechanisms including means for preventing two bowling balls from being simultaneously fed from a pair of adjacent ball elevators onto a common ball return runway servicing a pair of adjacent alleys with which the two ball elevators are associated.

Bowling alley installations are commonly arranged so that a single ball return runway services two adjacent alleys, the runway extending between the alleys from the pit to the players approach area. When an installation also includes automatic bowling pin spotting machines having bowling ball elevators arranged to lift bowling balls from the pits and transfer them onto the runway, there is a possibility that, if two balls land in adjacent pits at about the same time, such balls could be simultaneously delivered, in the absence of any preventative mechanism, onto the common return runway and thereby cause the machine to jam, with resultant damage, or cause the delivered balls to fall off the runway.

Accordingly, a general object of the invention is to provide a mechanism for preventing two. bowling balls from being fed simultaneously from two adjacent bowling ball elevators onto a common bowling ball return runway associated with such elevators.

Another object is to provide an interlock for use with a plurality of ball elevators of the type which comprise a vertical ball elevating conveyor and a vertical track spaced from the conveyor so that a bowling ball is held between the conveyor and the track and is elevated by movement of the conveyor.

Still another object is to provide improved means for resiliently mounting a ball elevating belt whereby the mounting structure is relatively compact and biases the belt to maintain thereon a level of tension sufficient to enable the bowling ball to be elevated thereby.

Another object is to provide an interlock for a pair of ball elevators so constructed that, while a ball is being elevated by one of the elevators, another ball cannot be elevated by the same elevator nor can another ball be elevated by the other elevator.

In order that the manner in which these and other objects are attained in accordance with the invention can be understood in detail, reference is had to the accompanying drawings, which form a part of this specification, and wherein:

FIGURE 1 is a side elevational view, partly in vertical section, of mechanism constructed in accordance with one embodiment of the invention;

FIGURE 2 is a front elevational view, partly in vertical section, of FIGURE 1;

FIGURE 3 is a front elevational view similar to FIG- URE 2 but with some of the details omitted for clarity illustrating the relationship of the elevators when a ball is elevated by one of the elevators;

FIGURE 4 is a fragmentary top plan view, partly in horizontal section, of FIGURE 1; and

FIGURE 5 is a top plan view of FIGURE 1.

Referring now to the drawings in detail, the illustrated embodiment of the invention is shown in association with a bowling alley installation of the type having a pair of adjacent pits P1 and P2 separated by a pair of parallel spaced kickbacks K1 and K2 which extend along the adjacent sides of pits P1 and P2 respectively.

3,2319% Patented Mar. 1, 1966 Mounted in pits P1 and P2 are a pair of conveyors C1 and C2, respectively, each of the conveyors including a pit-wide endless belt 10 of a suitable flexible material, such as rubber-impregnated canvas, which has a high coefficient of friction. Each belt passes over a pulley 11 located toward the rear of the pit and driven from a gear reduction motor 13 by a belt 12 so that the upper run of belt 10 moves toward the rear of the associated pit, whereby any bowling balls or bowling pins which fall or are swept into the pit from the alley come to rest on the upper run of the belt and are carried toward the rear of the pit.

Also mounted respectively in pits P1 and P2 are two backstops B1 and B2, each of the backstops being provided with a shock absorbing mechanism 14. Connected to the upper end of each backstop B1 and B2 is a pit-wide, anti-flyback curtain 22 which prevents flying pins from flying upwardly where they might damage parts of the pinspotting mechanism, or back onto the alley. Each of the backstops includes a lower straight edge 15 which extends for substantially the full length of the backstop, and a cutout providing an arcuate edge 16 located at one end of the backstop. Each of straight edges 15 is spaced above belt 19 by a distance greater than the maximum diameter of a bowling pin but less than the diameter of a bowling ball, whereby bowling pins can pass beneath the straight edges 15 but bowling balls cannot. Arcuate edges 16 have radii of curvature greater than that of the radius of curvature of the outer surface of a bowling ball, the arcuate edges being spaced above belts 1t) at a distance sufficiently great to permit bowling balls to pass beneath the backstop.

Conveyors C1 and C2 are arranged so that the upper runs of belts 10 are inclined toward the sides of the pits adjacent to arcuate edges 16 so that balls carried by the belts and engaged with the backstops move toward predetermined sides of the pits, hereafter referred to as the delivery sides, due to the combined effect of gravity and the motion of the belts.

Also mounted in pits P1 and P2 are a pair of pin elevators PE1 and PEZ and a pair of ball elevators BB1 and BB2, each pin elevator extending across the rear of its associated pit and each ball elevator being located adjacent to adjacent sides of its associated pit and directly behind the delivery side of its associated conveyor. EX- tending transversely across the rear of the pits and in front of each of the pin elevators is a pin chute 17 over which the bowling pins pass as they are discharged from the conveyor and are delivered to the pin elevators. Associated with each of the conveyors are two plows 18 (only one of which is shown in each pit) which direct pins toward the center of the pin chute and toward the delivery or receiving station of the pin elevator.

Pins passing beneath arcuate edges 16 usually continue to move rearwardly for discharge by conveyors 10 into elevators PE1 and PE2. In order to insure further the continued delivery of pins passing beneath arcuate edges 16 and to prevent any possible jamming with balls to be elevated by ball elevators BB1 and BB2, there may be provided means for deflecting such pins onto the adjacent plow 18 so that such pins are delivered without interruption to the pin elevators. In the illustrated embodiment, such means comprises a filler strip deflector 19 attached to the adjacent kickback and a resilient flap 20 which is mounted on the adjacent kickback and extends across the path of movement of bowling balls and pins. Each flap is sufficiently yieldable to allow a bowling ball passing thereby to bend the flap back against the kickback and allow the bowling ball to pass freely. On the other hand, each flap is sufiiciently stiff so that bowling pins which engage the flap are directed onto the adjacent plow 18, the momentum of the pins being ineffective to bend the flap backwardly in the manner that a bowling ball does.

Mounted beneath the upper run of each of belts is a rearwardly extending guide chute 21 so arranged that, when a bowling ball rests on the upper run of belt '10 above the guide chute, the belt is deformed, as shown in FIG. 3, to provide a rearwardly extending trough aligned with the receiving portion of the associated ball elevator.

Each of the ball elevators BEl and BE2 is of a type similar to that disclosed in copending application Serial No. 15,297, filed March 16, 1960, by George Fried, and now Patent No. 3,107,917. The ball elevators are identical so that only one need be described in detail.

Ball elevator BEI comprises a vertical conveyor 24- and a vertical track 25. Conveyor 24 includes an endless belt 26 which passes around a lower driven pulley 27, over a pulley 28 located above pulley 27 and operative to increase the arc of contact between belt 26 and pulley 27, and around an upper, idler pulley 29 mounted on the end of a pivoted arm 30 biased by a helical compression spring 3 1 to maintain sufficient tension on belt 26 to allow a bowling ball to be elevated by movement of the belt. The axes of pulleys 27, 28 and 29 are parallel and extend transversely of the pit, the pulleys being located so that the forward run of belt 26 is spaced from track by a distance less than the diameter of a bowling ball. Pulley 27 is driven by a belt 32 which, in turn, is driven by motor 13, so that the forward run of belt 26 moves upwardly, in the direction of the arrow as shown in FIGURE 1.

As best seen in FIGURES l and 2, arm 36 is pivoted at its rear end on a pivot pin 33 mounted on a frame member 34 extending upwardly from kickback K1. The forward end of arm supports a shaft 35 upon which pulley 29 is rotatably mounted. Frame member 34 also includes a portion disposed beneath the free end of arm 30, which portion has an upwardly extending cylindrical projection 36 disposed opposite to a similarly shaped projection 37 which extends downwardly from the forward or free end of arm 30, the projections extending into the adjacent ends of springs 31 to maintain the spring in operative position. As previously indicated, spring 31 maintains sufiicient tension on belt 26 so that a bowling ball can be elevated thereby. Spring 31 is further operative to allow arm 39 to be moved through a limited arc in clockwise direction, as viewed in FIG- URE 1, when a bowling ball is gripped between belt 26 and track 25.

Track 25 is elongated and preferably forwardly inclined from the vertical at a slight angle, as shown in FIGURE 1, the track being supported by a pair of pivoted links 39 and 40 extending forwardly of track 25 and mounted on frame member 41 secured to kickback K1. Links 39 and 40 are of equal length and are parallel so that track 25 moves in parallel fashion through a vertical are having an axis that extends transversely of the pit. Attached to track 25 for movement therewith is a guide rail 42 which extends along one side of the track, the guide rail and the track being shaped so that a bowling ball being elevated by ball elevator BB1 cannot shift laterally of track 25 and become disengaged from belt 26.

Attached to the upper and lower ends of and forming a part of track 25 are a pair of ball guide elements 43 and 44, respectively, in the form of rubber blocks. As illustrated in FIGURE 2, block 44 includes a horizontal, downwardly facing surface 45 and a pair of divergent downwardly inclined surfaces 46, FIGURES 2 and 3, so arranged that as a bowling ball passes beneath the block, each of the surfaces 45 and 46 engages the bowling ball and thereby centers and guides the bowling ball as it passes beneath the block. Such centering action properly aligns the bowling ball for pick up by the elevator BB1. Upper block 43 is similarly shaped so that, as a bowling ball passes over upon discharge from ball elevator BEl, the ball is guided in alignment with the adjacent infeed portion of track T.

Links 39 and 40 allow track 25 to move between a normal position, a ball elevating position and an inoperative position. When track 25 is in the normal position, the lower end of the track, i.e., the bottom of block 44, is spaced above belt 10 by a distance less than the diameter of but greater than the radius of a bowling ball. When track 25 is in the ball elevating position, the lower end thereof is sufliciently close to belt 19 to prevent any additional balls from moving beneath the track so long as the track remains in the ball elevating position. When track 25 is in the inoperative position, the lower end thereof is spaced above the belt a distance large enough so that, if a ball is delivered thereto, the ball cannot move the track to its ball elevating position. That is, when track 25 is in the inoperative position, a ball delivered to ball elevator BB1 is precluded from being elevated.

Similarly, ball elevator BB2 comprises a conveyor 48 and a track 49 identical in construction and operation to conveyor 24 and track 25.

As best seen in FIGURE 5, a ball return runway or track T includes a pair of converging infeed portions 50 and 51, the rear portions of which are aligned with the delivery ends of the ball elevators BB1 and BE2 and the forward portions of which merge into a common portion 52. Track T is inclined downwardly and forwardly so that the balls delivered thereto roll under the influence of gravity and are returned to the players approach area of the alley in the usual fashion.

Extending forwardly from tracks 25 and 4.9 are a pair of pins 53 and 54, respectively, which overlie opposite ends of a bar 55 pivotally mounted at its center on a pivot pin 56 supported on a frame member 57 extending across the tops of kickbacks K1 and K2. The axis of pin 56 extends forwardly and is inclined upwardly and lies substantially parallel to the positions occupied by links 39 and 49 when tracks 25' and 49 are in their normal positions. Bar 55 also includes an upwardly extending portion 58 provided with a bolt to which the lower ends of a pair of upwardly divergent helical tension springs 59 and 60 are connected, the upper ends of the springs being secured to a frame member 61. Springs 59 and 60 are identical and bias bar 55 toward a balanced position wherein the bar is horizontal, such position being shown in FIGURE 2. In this portion, bar 55 engages both of pins 53 and 54. Springs 59 and 60, acting through bar 55 and pins 53 and 54, also bias tracks 25 and 49 upwardly against their own weight and toward their normal positions, which positions are those illustrated in FIGURE 2.

Operation Assume that there are no bowling balls in either of the pits, and the conveyors C1 and C2 and 24 and 48 are in operation, tracks 25 and 49 being in their normal positions, shown in FIGURE 2, due to the bias of springs 59 and 60.

Since the operation of both the bowling ball elevators is identical, only one need be described in detail. With reference to bowling ball elevator BEI, when a bowling ball lands in pit P1, it is moved toward the delivery side of the conveyor and passes beneath edge 16 of backstop B1. Belt 10 carries the bowling ball beneath the backstop and into engagement with block 44 of track 25. The frictional engagement between the bowling ball and belt 10 and block 44 causes the ball to raise track 25 until the ball passes beneath the block and into engagement with the forward, upwardly travelling run of belt 26. At this point, the combined motion of belts 10 and 26 rotates the bowling ball so that track 25 is moved downwardly into its ball elevating position. Simultaneous with such movement, the bowling ball is clamped between the belt 26 and track 25, so that the ball is rolled upwardly along the track by belt 26. When the ball reaches block 43, the

tension of belt 26 pushes the ball forwardly over block 43 and onto infeed portion 50 of track T thereby accelerating its movement therealong for return to the approach end of the alley (not shown). When track 25 is in the ball elevating position, the upper end of block 43 is aligned with the receiving end of the infeed portion 50.

It should be noted that, during the elevation of the ball, arm 30 is pivoted downwardly slightly so that, upon discharge of the ball onto track T, spring 31 causes arm St) to swing counterclockwise (as viewed in FIGURE 1) upwardly to the position shown in FIGURE 1. As a bowling ball moves under block 44, it lifts track 25 and continues its movement into engagement with belt 26. Track 25 then moves downwardly a short distance so that the ball is pressed by belt 26 against block 44. The continuous movement of belt 26 causes the ball to move upwardly, squeezing block 44, onto track 25. This movement results in a positive downward displacement of track 25 to its lowermost or ball lifting operative position. Upper links 40 which are pivotally mounted in legs 74 of channel '76 attached to the frame, designated generally F, are provided with shoulders 70 adapted to engage the center web of channel 76 and limit the downward movement of track 25 to a position such that it blocks the entry of a ball into the ball lifting device including track 25 and belt 26 until a ball on track 25 has been delivered onto runway T and track 25 has again been positioned to receive such ball.

The upward movement of track 25 causes pin 53 to move away from the adjacent end of bar 55. Since bar 55 is in a balanced position due to springs 59 and 60, the movement of pin 53 away from the bar does not cause or allow movement of the bar. However, as track 25 descends, due to the action of belt 26 in rolling a ball upwardly along track 25, pin 53 bears downwardly on the adjacent end of bar 55 and thereby causes the bar to rotate from its normal position, shown in FIGURES 2, counterclockwise to the position shown in FIGURE 3. This movement of bar 55 decreases the force applied by spring 59 and increases the :force of spring 61 whereby, when the ball is discharged from elevator BEI, the bias of spring on rotates bar 55 toward its normal position and, in so doing, raises track 25 to its normal position. The movement of bar 55 into the position shown in FIGURE 3 causes the other end of the bar to bear against and raise pin 54, thereby raising track 49 to the inoperative position as shown in FIGURE 3. In this position, the lower end of track 49 is spaced above conveyor C2 by a distance great enough so that, should a ball, which lands in pit P2 while a ball is being elevated by ball elevator BEL move to the delivery side of ball elevator BB2, the ball will engage conveyor 26 and simply rotate at the junction of conveyor C2 and conveyor 26. Then, when the ball being elevated is discharged from ball elevator 3E1, and bar 55 returns to its normal position, track 49 moves downwardly due to its own weight. As track 49 moves downwardly into its normal position, it engages the bowling ball at the base of ball elevator BB2, so that the ball moves track 49 to its ball elevating position whereby that ball will be elevated by ball elevator BB2 and discharged onto track T. During such elevation, track 25 is raised in a manner similar to that just described with reference to track 49 so that ball elevator BET cannot elevate any balls delivered thereto. Then, when the hall is discharged by ball elevator BB2, track 25' moves downwardly, and track 49 moves upwardly, to their normal positions. If a bowling ball lands in pit P2 first, the operation is the reverse of that described above.

While only a single embodiment has been shown, it will be apparent to those skilled in the art that many changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims.

What is claimed is:

1. For use in a bowling alley installation having a common ball return runway servicing two adjacent alleys each having a pit at one end thereof, the combination of: a pair of ball elevators each mounted to receive balls in a different one of said pits for elevating bowling balls from a pit directly to said runway; conveying means in each of said pits for delivering balls to its corresponding elevator, and means for rendering one of said elevators inoperative to elevate a bowling ball from its COI'ICSPOHCL ing pit while the other elevator is elevating a bowling ball delivered thereto by said conveying means.

2. For use in a bowling alley installation having a pair of ball receiving stations and a single ball delivery station, the combination of: a pair of ball handling devices each adapted to receive a bowling ball at a different one of said ball receiving stations and deliver such ball to said ball delivery station, each of said ball handling devices comprising elongated track means along which a ball is rolled, means mounting each of said elongated track means for movement between a plurality of positions including a normal position wherein said device is positioned to receive a bowling ball, a ball conveying position wherein said device is operative to convey a ball to said ball delivery station, and an inoperative position wherein said device is inoperative to convey a bowling ball, an endless and conveyor having an operative lap spaced from said track means and cooperable therewith to roll a bowling ball along said track means when said track means is in said ball conveying position; and means interconnecting said devices so that when one of said track means is in said ball conveying position, the other of said track means is in said inoperative position.

3. For use in a bowling alley installation having a return runway means servicing a pair of adjacent alleys each having a pit at one end thereof, the portion of the runway means adjacent to said pits being elevated with respect to said pits, the combination of: a pair of ball elevators for elevating bowling balls in said pits and delivering such balls to said runway, said elevators being adapted to be mounted in said pits adjacent to adjacent sides of said pits; means for delivering to said elevators bowling balls which are in said pits; each of said elevators comprising a continuously driven conveyor, a track extending along said conveyor and arranged so that adjacent portions of said track and said conveyor are spaced a distance less than the diameter of a bowling ball, and means mounting said track for movement between a plurality of positions including a normal position wherein a ball delivered to said elevator moves into engagement with both said track and said conveyor and causes said track to be moved to a ball elevating position wherein a ball is engaged by both said track and said conveyor due to movement of said conveyor, and an inoperative position wherein said track is spaced from a ball delivered to said elevator and thereby precludes such ball from being elevated so long as said track remains in said inoperative position; and means interconnected with the tracks of each of said conveyors and operative to move one of said tracks to its inoperative position in response to movement of the other of said tracks to its ball elevating position, whereby only one ball at a time can be elevated by said elevators.

4. The combination of claim 3 wherein each of said conveyors comprises an endless belt, a driven pulley for driving said belt, an idler pulley engaged with said belt, and means for resiliently mounting said idler pulley, said means comprising a pivoted arm supporting said idler pulley, frame means supporting said arm and including a portion disposed from the free end of said arm, and a compression spring engaged with said portion and said arm and biasing said idler pulley to maintain on said belt sufficient tension to enable a bowling ball to be elevated.

5. The combination of claim 3 wherein each of said tracks is further operative when it is in said ball elevating position to prevent any additional balls from moving into engagement with both each said track and its associated conveyor.

6. The invention defined in claim 2 wherein said means interconnecting said devices comprises operating means carried by each of said track means and a pivoted interlock bar engageable by said operating means to maintain one of said track means in operative position while the other track means is operatively engaged by a ball being elevated.

7. A bowling ball elevating system having a pair of ball receiving stations for receiving balls from the pits of two side by side bowling alleys and a ball delivery station to which said balls are delivered, comprising a pair of ball handling devices, means mounting each of said devices at a dilTerent one of said ball receiving stations to receive balls from said pits and deliver said balls upwardly to said ball delivery station, each of said ball handling devices including a substantially vertical track, means mounting each of said tracks for movement between a normal position wherein said device is ready to receive a bOWling ball, an operative ball conveying position wherein said track is moved downwardly in response to the travel of a bowling ball upwardly along said track, and a ball blocking position wherein said track prevents the movement of a bowling ball to a receiving station for upward movement therealong, and an endless con veyor having a ball engaging and conveying lap spaced from said track and cooperable therewith to move a bowling ball upwardly along said track and force said track down to said operative position whereby said conveyor can roll a ball upwardly thereon to said delivery station and also locate said track in said blocking position and thereby prevent the movement of another ball in the pit into position to be engaged by said belt against movement upwardly thereby along said track.

8. The invention defined in claim 7 including means interconnecting said devices so that when one of said tracks is in said operative ball conveying position, the other of said tracks is incapacitated, whereby the simultaneous delivery of balls from each of said pits is prevented.

9. For use in a bowling alley installation having a pair of adjacent alleys each having a pit at one end thereof, a pair of kickbacks extending between said pits and a common return runway servicing both of said alleys, said runway having a receiving end spaced above said pits, the combination of a pair of bowling ball elevators adapted to elevate bowling balls in said pits and deliver such balls to said runway, said elevators being adapted to be mounted in said pits adjacent to said kickbacks; means for delivering to said elevators bowling balls which are in said pits; each of said elevators comprising a continuously driven conveyor, a track extending along said conveyor, and means mounting said track for movement between a plurality of positions including a normal position, a ball elevating position and an inoperative position; each of said tracks and said associated conveyors being arranged so that when said track is in said normal position a bowling ball delivered to the associated elevator moves into engagement with both said track and said conveyor whereby the motion imparted to such ball causes said track to move to its ball elevating position, when said track is in said ball elevating position a ball engaged with both said track and said conveyor is elevated to said runway, and when said track is in said inoperative position a ball delivered to the associated elevator is precluded from being elevated by such elevator so long as said track remains in said inoperative position; and means engageable with each of said tracks and operative to move each one of said tracks to its inoperative position upon movement of the other one of said tracks to its ball elevating position.

10. The combination of claim 9 wherein said last mentioned means comprises an elongated member pivoted at a point intermediate to its ends, and means biasing said elongated member toward a normal position; and said tracks each include a portion engageable with one of the ends of said member.

11. The combination of claim 10 wherein said member is pivoted about an axis that extends horizontally of said alleys, and said tracks are movable through parallel arcs having their centers of curvature lying along a line that extends transversely of said alleys.

12. For use in a bowling alley installation having a common ball return runway servicing two adjacent alleys, each having a pit at one end thereof, the combination of 2 a pair of ball elevators each mounted to receive balls from a difierent one of said pits for elevating bowling balls to said runway; means for rendering one of said elevators inoperative to elevate a bowling ball while the other elevator is elevating a bowling ball, a backstop in each of said pits, each of said backstops having an opening through which balls may move, ball and pin conveying means in the pit of each alley, said conveying means having a ball and pin conveying and supporting surface positioned beneath said backstop a distance greater than the maximum diameter of a bowling pin and less than the maximum diameter of a bowling ball, whereby balls may pass said backstops only through said openings, and guide means beneath said surface of said conveying means for guiding balls through said openings to said ball elevators, each of said conveying means comprising a flexible endless pit-wide conveyor belt, said conveyor belts being deflected by balls resting thereon into said guide means to form guide troughs along which said balls can roll through said openings in said backstops to said ball elevators for elevation thereby to said runway.

References Cited by the Examiner UNITED STATES PATENTS 2,531,167 11/1950 Simpson 273-43 2,697,605 12/ 1954 Montooth et al 273-43 2,765,172 10/1956 Zuercher et al 273-49 2,776,138 l/l957 Holloway et al 273-49 DELBERT B. LOWE, Primary Examiner. 

1. FOR USE IN A BOWLING ALLEY INSTALLATION HAVING A COMMON BALL RETURN RUNWAY SERVICING TWO ADJACENT ALLEYS EACH HAVING A PIT AT ONE END THEREOF, THE COMBINATION OF: A PAIR OF BALL ELEVATORS EACH MOUNTED TO RECEIVE BALLS IN A DIFFERENT ONE OF SAID PITS FOR ELEVATING BOWLING BALLS FROM A PIT DIRECTLY TO SAID RUNWAY; CONVEYING MEANS IN EACH OF SAID PITS FOR DELIVERING BALLS TO ITS CORRESPONDING ELEVATOR, AND MEANS FOR RENDERING ONE OF SAID ELEVATORS INOPERATIVE TO ELEVATE A BOWLING BALL FROM ITS CORRESPONDING PIT WHILE THE OTHER ELEVATOR IS ELEVATING A BOWLING BALL DELIVERED THERETO BY SAID CONVEYING MEANS. 